1. Field of the Invention
The present invention relates generally to surgical devices and, more particularly, to a ring applicator and method for applying one or more elastic rings to anatomical tissue structures such as the fallopian tubes.
2. Discussion of the Background Art
A variety of procedures have been developed to accomplish female sterilization by obstructing the fallopian tubes in order to prevent fertilization of the ova. The traditional procedure involves tying off each tube with ligatures and then cutting between the ligatures to permanently remove a section of the tubing. Another type of procedure utilizes electrocautery instruments to burn through and permanently seal each of the fallopian tubes. These procedures involve significant discomfort for the patient, and highly skilled personnel are required to complete the operation successfully. With respect to cauterization, in particular, there is the possibility of inadvertently burning other organs of the body and, for example, accidentally perforating the bowel.
The foregoing procedures are also undesirable in that they effect a sterilization which is permanent and cannot easily be reversed. In theory, plastic or metal clips can be applied to each tube in order to effect a sterilization which can be reversed; however, in practice, the clips have sometimes fallen off, thereby rendering the sterilization ineffective. Another type of reversible procedure which has gained wide acceptance in many parts of the world involves drawing the fallopian tube into a loop or knuckle within a tubular member carrying an elastic ring and slipping the elastic ring onto the loop in order to obstruct or ligate the tube. Typically, a forceps is used to draw the fallopian tube into a loop within a first tubular member. The first tubular member containing the loop is then caused to move axially relative to a second tubular member disposed telescopically around the first tubular member such that an elastic ring is forced off the distal end of the first tubular member onto the midsection of the loop, thereby occluding the fallopian tube.
A number of ring applicators have been developed to ligate tubular organs such as the fallopian tube. A first type of ring applicator, exemplified by U.S. Pat. Nos. 3,911,923 and 4,374,523 to Yoon, and U.S. Pat. Nos. 4,257,420 and 4,471,766 to Terayama, is designed to ligate only one fallopian tube at a time. Thus, in such devices, after one of the fallopian tubes has been occluded by placing an elastic ring around a loop formed in the fallopian tube, it is necessary to completely withdraw the instrument from the patient and reload the instrument with another elastic ring to ligate the second fallopian tube. Such a technique is not only time consuming, but also unduly complicates the tubal ligation procedure and, in some instances, can increase the chance of infection.
Another type of ring applicator, exemplified by U.S. Pat. No. 4,230,116 to Watson and U.S. Pat. No. 4,548,201 to Yoon, permits multiple rings to be carried at the distal end of a first tubular member disposed telescopically within a second tubular member, but relies on user skill to eject the rings individually by retracting the first tubular member partially to eject the first ring and fully to eject the second ring. A disadvantage of this type of ring applicator is that it is difficult to determine when the first ring has been ejected to know when to stop retracting the first tubular member. It is therefore possible for inexperienced or unskilled operators to eject both rings onto the first fallopian tube thereby requiring withdrawal of the instrument from the operative site for reloading before the second fallopian tube can be ligated.
Yet another type of ring applicator, exemplified by U.S. Pat. Nos. 4,226,239 and 4,493,319 to Polk, et al., utilizes an adjustable stop to limit displacement of the first tubular member relative to the second tubular member to an appropriate amount for each ring. In these devices, movement of the first and second tubular members is linked to handles, with the stop being positionable between the handles to prevent full retraction of the first tubular member in the case of the first ring and being removable from between the handles to permit full retraction of the first tubular member for ejecting the second ring. U.S. Pat. No. 4,493,319 also discloses a locking mechanism for preventing relative movement between the first and second tubular members to facilitate loading of elastic rings. However, the locking mechanism operates independently of the adjustable stop and does not allow the forceps to be fully deployed when in use.
A disadvantage of prior art ring applicators in general is that ejection of the rings occurs automatically with retraction of the forward or distal handle thereby limiting the ability of the surgeon to control the order and timing of the steps involved in the procedure. Another disadvantage of prior art ring applicators is that these devices do not permit rings to be ejected until the anatomical tissue structure has been drawn into the first tubular member a predetermined distance which is fixed. Depending on the type of anatomical tissue structure being ligated and other operating conditions, it may be desirable to retract greater or shorter lengths of tissue prior to ejecting a ring. Still another disadvantage of prior art ring applicators is that it is typically not possible to observe the anatomical tissue once it has been retracted into the tubular member in order to determine whether the tissue is properly positioned prior to ejecting an elastic ring.
Accordingly, it is a primary object of the present invention to overcome the abovementioned disadvantages of the prior art and to improve ring applicators having adjustable stops which limit axial movement of telescoping members to permit multiple elastic rings to be applied to anatomical tissue structures in a reliable manner.
It is another object of the present invention to simplify operation of a ring applicator having an adjustable stop and a locking mechanism for preventing relative axial movement of the telescoping members during ring loading by incorporating a locking mechanism into the adjustable stop.
It is yet another object of the present invention to permit independent tissue retraction and ring ejection operations to be performed with a ring applicator by coupling a forceps with a first handle and telescoping members with a second handle axially movable relative to the first handle and pivotably movable relative to the telescoping members.
It is an additional object of the present invention to assure proper placement of anatomical tissue structures within tubular members of a ring applicator prior to ejecting a ring by providing the tubular members with transparent tips having scale markings for comparison with the tissue structures.
Yet another object of the present invention is to enable surgeons to determine the relative lengths of grasping members used to draw anatomical tissue structures into a tubular member of a ring applicator in order to prevent improper use of the grasping members which may cause damage to the anatomical tissue structures.
The present invention has another object in permitting an elastic ring to be ejected onto an anatomical tissue structure which has not been fully drawn into a first tubular member of a ring applicator so that, for example, the ring applicator can be used to ligate anatomical tissue structures of various sizes.
The aforesaid objects can be achieved individually or in combination, and it is not intended that the present invention be construed as requiring two or more of the objects to be achieved in combination unless expressly required by the attached claims.
The present invention is generally characterized in a ring applicator for applying elastic rings to anatomical tissue during surgical procedures including an inner member with a forceps movably disposed within a middle tubular member having a distal portion configured to hold an elastic ring in an expanded state and a proximal portion with a plurality of longitudinally spaced abutment surfaces or steps. The middle tubular member is movably disposed in an outer tubular member, and an adjustable stop mechanism is mounted on the proximal end of the outer tubular member to limit axial movement of the outer tubular member relative to the middle tubular member by aligning a stop member with a different abutment surface in each stop position. A distal handle is preferably connected with the inner member via slots in the outer and middle tubular members, and a proximal handle is preferably pivotally connected to the middle tubular member via a slot in the outer tubular member. In a preferred embodiment, a pusher has a proximal end pivotally connected with the proximal handle and a distal end movable between a latched position where the distal end of the pusher protrudes into apertures in the outer and middle tubular members to prevent pivotal movement of the proximal handle and an unlatched position where the distal end of the pusher is disengaged from the aperture in the middle tubular member to permit pivotal movement of the proximal handle in order to move the outer tubular member axially relative to the middle tubular member to eject an elastic ring.
Another aspect of the present invention is generally characterized in a ring applicator for applying elastic rings to anatomical tissue during a surgical procedure including an outer tubular member having an aperture formed therein, a middle tubular member movably disposed within the outer tubular member and having an aperture formed therein, and an elongate inner member movably disposed within the middle tubular member and having a forceps at a distal end. A distal handle is connected to the inner member via slots in the outer and middle tubular members, and a proximal handle is pivotally connected to the middle tubular member via a slot in the outer tubular member. The proximal handle carries a pusher having a proximal end pivotally connected with the proximal handle and a distal end movable between a latched position where the distal end of the pusher protrudes into the apertures to prevent pivotal movement of the proximal handle and relative axial movement between the outer and middle tubular members, and an unlatched position where the distal end of the pusher is disengaged from the aperture in the middle tubular member to permit pivotal movement of the proximal handle in order to move the outer tubular member axially relative to the middle tubular member to eject a ring. In a preferred embodiment, the pusher includes a cam follower, such as a peg, which slides along a cam surface in the distal handle when the handles are moved toward one another, thereby causing the pusher to become disengaged from the middle tubular member. The cam surface can, for example, be defined by a knuckle slide movably disposed in the distal handle. Moving the knuckle slide relative to the distal handle allows a ring to be ejected when the handles are axially spaced from one another so that, for example, anatomical tissue structures of various sizes can be ligated. When provided, the knuckle slide can include a ratcheting feature which is released in response to engagement of the pusher with the knuckle slide.
Yet another aspect of the present invention is generally characterized in a ring applicator for applying elastic rings to anatomical tissue in surgical procedures including an outer tubular member, a middle tubular member movably disposed within the outer tubular member and having a distal portion configured to receive an elastic ring in an expanded condition, and an elongate inner member movably disposed within the middle tubular member and including a pair of opposed grasping members at a distal end, the grasping members having pivot arms of unequal length with distal tips oriented transverse to the arms such that one of the tips is disposed proximally of the other tip when the grasping members are in a closed condition, wherein at least a portion of one of the grasping members has a color allowing the one grasping member to be visually distinguished from the other grasping member when the grasping members are viewed remotely via an endoscope.
An additional aspect of the present invention is generally characterized in a ring applicator for applying elastic rings to anatomical tissue in surgical procedures including an outer tubular member, a middle tubular member movably disposed within the outer tubular member and having a distal portion configured to receive an elastic ring in an expanded condition, and an elongate inner member movably disposed within the middle tubular member and including a forceps at a distal end for grasping anatomical tissue and drawing the tissue into the middle tubular member, wherein the outer tubular member and the middle tubular member includes a transparent distal portion with scale markings for measuring anatomical tissue drawn into the middle tubular member.
Still another aspect of the present invention is generally characterized in a method of applying elastic rings to anatomical tissue during surgical procedures using a ring applicator having a middle tubular member disposed within an outer tubular member, and an inner member with forceps disposed within the middle tubular member, the method including the steps of positioning the middle tubular member to protrude distally from the outer tubular member, adjusting a stop mechanism on the proximal end of the outer tubular member to engage a first of a plurality of longitudinally spaced abutment surfaces or steps at a proximal end of the middle tubular member such that the middle tubular member is prevented from moving axially relative to the outer tubular member, loading elastic rings onto the distal end of the middle tubular member, inserting the ring applicator into the body, grasping a first anatomical tissue structure using the forceps, pulling the tissue into the middle tubular member, adjusting the stop mechanism on the proximal end of the outer tubular member to position the stop member proximally of a second abutment surface along the proximal portion of the middle tubular member such that the outer tubular member can move axially about one ring width relative to the middle tubular member to eject a first ring from the distal end of the middle tubular member onto the tissue, and releasing the first anatomical tissue structure from the middle tubular member. A plurality of elastic rings can be loaded onto the distal portion of the middle tubular member during the loading step and, in a preferred embodiment, the method further includes the steps of grasping a second anatomical tissue structure using the forceps, drawing the second anatomical tissue structure into the middle tubular member, adjusting the stop mechanism on the proximal end of the outer tubular member to position the stop member proximally of a third abutment surface along the proximal portion of the middle tubular member such that the outer tubular member can move axially about two ring widths relative to the middle tubular members, ejecting a second elastic ring from the distal end of the middle tubular member onto the second anatomical tissue structure by moving the outer tubular member distally relative to the middle tubular member until the stop member contacts the third abutment surface, and releasing the second anatomical tissue structure from the middle tubular member.
Yet another aspect of the present invention is generally characterized in a method of applying elastic rings to anatomical tissue during surgical procedures using a ring applicator having a middle tubular member disposed within an outer tubular member, an elastic ring mounted on a distal portion of the middle tubular member, and an inner member with a forceps disposed within the middle tubular member, the forceps having opposed grasping members of unequal length and of different color, the method including the steps of inserting a distal end of the ring applicator into a body cavity, spreading the grasping members of the forceps apart, observing the color of the grasping members to determine which grasping member is shorter, positioning the anatomical tissue proximally of the tip of the shorter grasping member, grasping the anatomical tissue using the forceps, pulling the anatomical tissue into the middle tubular member using the forceps, and ejecting a ring from the middle tubular member onto the anatomical tissue by moving the outer tubular member distally relative to the middle tubular member.
Still another aspect of the present invention is generally characterized in a method of applying elastic rings to anatomical tissue during surgical procedures using a ring applicator having a middle tubular member with a transparent tip disposed within an outer tubular member with a transparent tip, and an inner member with a forceps disposed within the middle tubular member, the method including the steps of inserting the ring applicator into a body cavity, grasping anatomical tissue using the forceps, pulling the anatomical tissue into the middle tubular member using the forceps, viewing the anatomical tissue through the transparent tips of the outer and middle tubular members, measuring the length of the anatomical tissue against scale markings on one or both of the transparent tips, and ejecting a ring from the middle tubular member onto the anatomical tissue by moving the outer tubular member distally relative to the middle tubular member.
A further aspect of the present invention is generally characterized in a method of applying elastic rings to anatomical tissue structures during surgical procedures using a ring applicator having a middle tubular member disposed within an outer tubular member and connected to a proximal handle, and an inner member with forceps disposed within the middle tubular member and connected to a distal handle. The method includes the steps of positioning the middle tubular member in a loading position where a distal end of the middle tubular member protrudes distally from the outer tubular member, locking the middle tubular member in the loading position, moving the forceps to a retracted position within the middle tubular member by sliding the proximal and distal handles together such that the handles abut one another, loading an elastic ring onto a distal portion of the middle tubular member, inserting the ring applicator into the body, moving the forceps to an extended position protruding from the middle tubular member by sliding the proximal and distal handles apart such that the handles are axially spaced from one another, positioning the forceps around a first anatomical structure, pulling the first anatomical tissue structure into the middle tubular member with the forceps by sliding the proximal and distal handles together such that the handles abut one another, unlocking the middle tubular member so that the outer and middle tubular members can move axially relative to one another, and ejecting the elastic ring onto the first anatomical structure by pivoting the proximal handle about the point of contact between the handles to cause the outer tubular member to move distally relative to the middle tubular member.
Another aspect of the present invention is generally characterized in a method of applying elastic rings to anatomical tissue structures during surgical procedures using a ring applicator having a middle tubular member disposed within an outer tubular and connected to a proximal handle, and an inner member with forceps disposed within the middle tubular member and connected to a distal handle. The method includes the steps of positioning the middle tubular member in a loading position where a distal end of the middle tubular member protrudes distally from the outer tubular member, locking the middle tubular member in the loading position, moving the forceps to a retracted position within the middle tubular member by sliding the proximal and distal handles together such that the handles abut one another, loading an elastic ring onto a distal portion of the middle tubular member, inserting the ring applicator into the body, moving the forceps to an extended position protruding from the middle tubular member by sliding the proximal and distal handles apart such that the handles are axially spaced from one another, positioning the forceps around a first anatomical structure, pulling the first anatomical tissue structure into the middle tubular member with the forceps by sliding the proximal and distal handles together such that the handles are axially spaced apart, moving a knuckle slide disposed within the distal handle proximally relative to the distal handle such that a proximal surface of the knuckle slide abuts the proximal handle, unlocking the middle tubular member so that the outer and middle tubular members can move axially relative to one another, ejecting the elastic ring onto the first anatomical structure by pivoting the proximal handle about the point of contact between the proximal handle and the knuckle slide to cause the outer tubular member to move distally relative to the middle tubular member.